Fox News' Trace Gallagher and Shannon Bream advanced the claim, touted by "gun advocates," that the "vast majority" of weapons used in Mexican drug cartels "are not coming from the United States." In fact, according to ATF's National Tracing Center, 90 percent of these weapons that could be traced originated from within the U.S.

On the March 27 edition of Fox News' The Live Desk, co-host Trace Gallagher stated that Attorney General Eric Holder "says" reinstituting the ban on assault weapons "would help in the battle with violence along the U.S.-Mexico border, but gun advocates say that's not right." Supreme Court correspondent Shannon Bream then asserted: "Absolutely. ... [T]hey say if you go to the border, if you talk to law enforcement agents who are there, working all along both sides of the border, and immigration officials as well, and ask them about this issue, they'll say the vast majority of guns, according to them, that are in Mexico being used in some of these drug cartels are not coming from the United States." At no point did Gallagher or Bream mention that statistics from the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) contradict the anecdotal claim of these "gun advocates." ATF and Drug Enforcement Administration (DEA) stated in recent congressional testimony that "according to ATF's National Tracing Center, 90 percent of the weapons [in Mexico] that could be traced were determined to have originated from various sources within the U.S."

In a joint prepared statement to the Senate Judiciary Subcommittee on Crime and Drugs, William Hoover, ATF assistant director for field operations, and Anthony P. Placido, DEA assistant administrator for intelligence, testified:

The southwest border is the principal arrival zone for most illicit drugs trafficked into the U.S., as well as the predominant staging area for the subsequent distribution of these drugs throughout the U.S. Guns are an integral part of these criminal enterprises; they are the "tools of the trade." Drug traffickers routinely use firearms against each other and have used these weapons against the Mexican military, law enforcement officials, and Mexican civilians. Because firearms are not readily available in Mexico, drug traffickers have aggressively turned to the U.S. as their primary source. Firearms are routinely being transported from the U.S. into Mexico in violation of both U.S. and Mexican law. In fact, according to ATF's National Tracing Center, 90 percent of the weapons that could be traced were determined to have originated from various sources within the U.S. One thing must remain clear in any discussion of violence in Mexico, or violence practiced by Mexican traffickers operating in the U.S.: drug gangs are inherently violent, and nowhere is this more true than in Mexico, where "Wild West"-style shootouts between the criminals and the cops, and elements of opposing trafficking groups are unfortunately considered normal.

From March 27 edition of Fox News' The Live Desk with Martha and Trace:

TRACE GALLAGHER (co-host): Well, in the meantime, Attorney General Eric Holder is battling for a gun fight, because the attorney general is reconsidering instituting a ban on assault weapons. Holder suggested bringing back the ban in response to the escalating drug violence in Mexico. He says it would decrease the flow of guns from the U.S. into Mexico.

But gun rights advocates say liberal Democrats are using the war next door to push for more restrictions on guns right here in the U.S. Shannon Bream is following this live from D.C. She's on RM-232.

And Shannon, the attorney general says the ban would help in the battle with violence along the U.S.-Mexico border, but gun advocates say that's not right.

BREAM: Absolutely. They think this is kind of a smokescreen, because they say if you go to the border, if you talk to law enforcement agents who are there, working all along both sides of the border, and immigration officials as well, and ask them about this issue, they'll say the vast majority of guns, according to them, that are in Mexico being used in some of these drug cartels are not coming from the United States. So these folks say the Second Amendment is now under attack by the attorney general.

They think he is trying to reinstate this ban on assault weapons as a way of, you know, getting gun control kind of maybe under the radar, because nobody looks at what's happening in Mexico and thinks that's a positive thing. It's obviously a very tragic situation. It gets people's attention. And so, you know, reinstating the ban in that arena makes it -- to a lot of people, it makes sense.

But folks are warning, if you care about your gun rights, you need to take another look at this, a closer look, Trace.

GALLAGHER: Shannon, how is this playing out on Capitol Hill?

BREAM: Well, you know, surprisingly -- not surprisingly, Republicans have said we're going to fight this. But a little bit more surprisingly, there is very strong, very organized Democratic opposition as well. We have a letter that came from 65 Democrats on the House side to the attorney general. We've got a quote from that.

It says: "It is hard to believe the ban would be any more effective in controlling crime by well-funded international drug traffickers, who regularly use grenade launchers, anti-tank rockets, and other weapons that are not available on the civilian market in the U.S."

So they say these guns that would be banned, that's not the only thing that these guys have in their arsenal. Also another letter went out from Senators [Max] Baucus [D-MT] and [Jon] Tester [D-MT], saying they will vigorously oppose any attempt to revive this ban.

So there is definitely organized bipartisan support against this that will be motivated to fight with the attorney general is proposing, Trace.

GALLAGHER: And I guess the bottom line here, Shannon, is does the administration have the support it needs?

BREAM: You know what? It doesn't sound like it right now because even top Democratic leaders -- Senate Majority Leader Harry Reid [D-NV] and also House Speaker Nancy Pelosi [D-CA] -- have come out and said, you know, we don't want to go down this path. We're not in favor of reinstating a ban here. What we need to do is enforce the gun laws that we have in effect right now.

And that's something you're hearing from people on both sides of this debate. They say the U.S. already makes it illegal for these guns to go across the border. Things have to be enforced on both sides of the border in order to make it effective. Let's do that. Let's make sure that's working before we pass an even broader law that's going to also need to be enforced. Let's start with what we have on the books now, Trace.

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